A Misissippian Echinoderm Site in Alabame

ABsTRACT-Abundancdea ta tabulated for different taxa at individual fossil sites may beuseful in future studies of taxonomic diversity in space and time. An echinoderm site,98 feet below the contact of the Upper Mississippian Monteagle Limestone and the HartselleSandstone on Weatherly Mountain approximately 7 miles south of Huntsville, Alabama,has yielded the following echinoderm genera: Onychaster Meek and Worthen, DiploblastusFay, Pentremites Say, Discocystis Gregory, Acrocrinus Yandell, AllocatillocrinusWanner, Aphelecrinus Kirk, Armenocrinus Strimple and Horowitz, Batocrinus Casseday,Cymbiocrinus Kirk, Decadocrinus Wachsmuth and Springer, Dichocrinus Miinster, DinotocrinusKirk, Linocrinus Kirk, Phanocrinus Kirk, Platycrinites Miller, Rhopocrinus Kirk,and Taxocrinus Phillips. Pentremites, Platycrinites, and Diploblastus are the dominantelements of the echinoderm fauna. Although detailed paleoecologic interpretations mustawait systematic quarrying of the site, the fauna probably was smothered and rapidlyburied. On the basis of stratigraphic position and the presence of Platycrinites penicillusMeek and Worthen, the fauna is probably late Genevievian

New Pennsylvanian (Moscovian) echinoderms from Xinjiang Uyghur Autonomous Region, western China

Abstract:The few Pennsylvanian echinoderm faunas reported from the Paleotethys are from China,Japan, and Australia. The Japanese and Chinese faunascontain camerates that are rare in Pennsylvanianfaunas worldwide.Genera of one monobathrid camerate, two disparids, five cladids, one flexible, oneblastoid, and one archaeocidarid are reported from the late Moscovian uppermost part of the QijiagouFormation or lowermost part of the Aoertu Formation in the Taoshigo Valley near Taoshuyuan Village,Xinjiang Uyghur Autonomous Region, China. They are here referred to as the Aoertu fauna, which ismost closely allied with Pennsylvanian crinoids reported from a slightly older fauna from the QijiagouFormation in the Taoshigo Valley and with faunas known from Japan and North America. Most taxa areidentified to the genus level and left in open nomenclature because of poor or partial preservation. Inaddition, camerate-ossicles and a cup of Synbathocrinus are reported from the early Moscovian part ofthe Sanquanzi Formation at Yamansu, southeast of the Taoshigo Valley. New taxa described are:Synbathocrinus labrus n. sp., Stellarocrinus qijiagouensis n. sp. and Metaperimestocrinus aoertuensi

Fourier Analysis of the Ostracode Margin

Abstract: Fourier analysis can be used as an objectivedescriptor of the ostracode margin. Results of the three examples suggest that the method explained may give information of interest to systematist. Use of Fourier analysis issuggested both for research on specimens and for study of illustrations from the literature

Stratigraphy and facies development of the marine Late Devonian near the Boulongour Reservoir, northwest Xinjiang China

Late Devonian to Early Carboniferous stratigraphic units within the ‘Zhulumute’ Formation, HonggulelengFormation (stratotype), ‘Hebukehe’ Formation and the Heishantou Formation near the BoulongourReservoir in northwestern Xinjiang are fossil-rich. The Hongguleleng and ‘Hebukehe’ formations are biostratigraphicallywell constrained by microfossils from the latest Frasnian linguiformis to mid-Famenniantrachytera conodont biozones. The Hongguleleng Formation (96.8 m) is characterized by bioclastic argillaceouslimestones and marls (the dominant facies) intercalated with green spiculitic calcareous shales. Ityields abundant and highly diverse faunas of bryozoans, brachiopods and crinoids with subordinatesolitary rugose corals, ostracods, trilobites, conodonts and other fish teeth. The succeeding ‘Hebukehe’Formation (95.7 m) consists of siltstones, mudstones, arenites and intervals of bioclastic limestone (e.g.‘Blastoid Hill’) and cherts with radiolarians. A diverse ichnofauna, phacopid trilobites, echinoderms(crinoids and blastoids) together with brachiopods, ostracods, bryozoans and rare cephalopods have beencollected from this interval. Analysis of geochemical data, microfacies and especially the distribution ofmarine organisms, which are not described in detail here, but used for facies analysis, indicate a deepeningof the depositional environment at the Boulongour Reservoir section. Results presented here concernmainly the sedimentological and stratigraphical context of the investigated section. Additionally, oneLate Devonian palaeo-oceanic and biotic event, the Upper Kellwasser Event is recognized near the sectionbase

A new species of Tiaracrinus from the latest Emsian of Morocco and its Phylogeny

Abstract: We describe a new species of the unusual crinoid Tiaracrinus, T. jeanlemenni sp. nov. from the latest Emsian of the famous mudmound locality Hamar Laghdad,Morocco. It differs from the previously known species inthe higher number of ribs and the vaulted rib-fields, which is corroborated by the comparison of simple quantitative characters and ratios as well as by the results of a clusteranalysis and a Principal Component Analysis. Based on the new material and the published specimens, we discuss the phylogeny of the genus and suggest that T. oehlerti and T.moravicus represent the ancestral forms of this small clad

New Ridged, Conical, Fissiculate Blastoid from the Permian of Timor

Abstract: Permian rocks from the Indonesian island ofTimor contain an abundant and diverse pelatozoanechinoderm fauna that was extensively monographed inthe first half of the twentieth century. Recent collectionshave produced specimens of Corrugatobastus savilli, n.gen. n. sp., the first genus of blastoid described from Timorin 70 years. Corrugatoblastus savilli is a ridged andfurrowed, conical, fissiculate blastoid with a highly unusualthecal morphology mimicking a small, solitary, rugosecoral. We have placed C. savilli in the family Codasterida,although it has several morphological features that areunique when compared to other genera in the family and to other blastoid genera regardless of familial assignment

Universal Elemental Homology in Glyptocystitoids, Hemicosmitoids, Coronoids and Blastoids: Steps Toward Echinoderm Phylogenetic Reconstruction in Derived Blastozoa

Abstract- Universal elemental homology (UEH) is used to establish homology of thecal plates and elements of the ambulacral system among clades of stemmed echinoderms by placing these structures into a testable hypothesis of homology. Here UEH is used to explorehypotheses of homology in blastoids, coronoids, Lysocystites,hemicosmitoids, and glyptocystitoids. This new approach to analyzehomology is particularly powerful in understanding the nature of thethecal plates of blastoids and how they relate to other taxa in a common nomenclatural lexicon. In blastoids, deltoids are interpretedas oral plates that are homologues to oral plates of glyptocystitoids and hemicosmitoids whereas side plates are interpreted to beambulacral floor plates. Thecal plates are homologous among blastoids, coronoids and Lysocystites but these morphologies cannotbe reconciled with plate circlets of glyptocystitoids and hemicosmitoids. A phylogenetic analysis of these taxa presents the origin of blastoids as sister taxon of coronoids within a testable seriesof homologies

Redescription of two Genera of blastoids from China

Abstract : In this paper we redescribe and reassign two genera of Chineseblastoids previously described by Mu (1955) and Chi (1943) based on our ownnew collections and those of other Chinese geologists. Mesoblastus tushanensisis reassigned to the Schizoblastidae from the Granatocrinidae based on the presence of ten spiracles and a separate anus and to the new genus Pinguiblastus. Previously Mississippian schizoblastids have been restricted toNorth America. Pinguiblastus provides a paleogeographic and evolutionarytransitional taxon between the North American schizoblastid genera and thevery abundant Permian faunas from Timor. Devonoblastus heitaiensis is reassigned to the new genus Sinoblastus, based on the presence of large exposed cryptodeltoids, a taxonomically significant character not found inDevonoblastus. This removes known occurrences of Devonoblastus from Asia

Climate instability and tipping points in the Late Devonian: Detection of the Hangenberg Event in an open oceanic island arc in the Central Asian Orogenic Belt

Sedimentary petrology and trace element geochemistry indicate that the Late Devonian to Early Carboniferous Heishantou Formation near Boulongour Reservoir (NW Xinjiang, China) was deposited on a steep slope, mid-latitude accreting island arc complex in an open oceanic system. Bulk 87Sr/86Sr ratios show excursion patterns that are consistent with excursions at the Devonian–Carboniferous (D–C) boundary in epicontinental margin sediments. Sedimentation rates for the Boulongour Reservoir sediments show highly variable rates that range from 0.5 cm/ky to 10 cm/ky, consistent with other Late Devonian sections and modern arc environments. Multiple whole rock geochemical proxies for anoxia and the size and distribution of pyrite framboids suggest the presence of the Hangenberg Event in the sediments associated with the D–C boundary, despite the lack of visible black shale. The presence of anoxia in an open ocean, island arc environment cannot be explained by upwelling of anoxic bottom waters at this paleolatitude, but can be explained by the global in?iction of oceanic shallow water eutrophication on to a climate system in distress

Early post-metamorphic, Carboniferous blastoid reveals the evolution and development of the digestive system in echinoderms

Inferring the development of the earliest echinoderms is critical to uncovering the evolutionary assembly of the phylum-level body plan but has long proven problematic because early ontogenetic stages are rarely preserved as fossils. Here, we use synchrotron tomography to describe a new early post-metamorphic blastoid echinoderm from the Carboniferous (approx. 323 Ma) of China. The resulting three-dimensional reconstruction reveals a U-shaped tubular structure in the fossil interior, which is interpreted as the digestive tract. Comparisons with the developing gut of modern crinoids demonstrate that crinoids are an imperfect analogue for many extinct groups. Furthermore, consideration of our findings in a phylogenetic context allows us to reconstruct the evolution and development of the digestive system in echinoderms more broadly; there was a transition from a straight to a simple curved gut early in the phylum's evolution, but additional loops and coils of the digestive tract (as seen in crinoids) were not acquired until much later